The invention concerns maritime transport of ore, in particular iron ore. It is a known fact that this type of transport represents a safety issue. The water contained in the ore can cause the sudden sliding or skidding of the ore in the hold, sometimes causing serious incidents.
Because of the large volumes concerned, iron ore is the first to be concerned, but the same problems can arise with other ores.
The applicant has found a solution to this problem in patent FR 2712 306 which proposes to incorporate a superabsorbent polymer (SAP) into the iron ore during loading.
The absorption of water by the polymer, combined with reduced porosity, prevents residual water from migrating towards the bottom of the hold.
Full-scale testing has produced the hoped-for results. However, the process is not widely used because of the cost and the implementation involved. On average, it requires between 50 and 100 tonnes of superabsorbent for between 100 and 150,000 tonnes of damp ore at 7-9%.
In addition, each ore behaves differently because of its particle size, its porosity, the impurity content and the loading method.
In practice, the SEP polymer is added to the conveyor belt used for loading the ship, throughout the loading process, to block the water in the mass.
Recent studies have revealed that despite consistent addition of SAP to the ore, probably because of the swelling speed of the superabsorbent, a large part of the water migrates to the bottom of the hold and can cause incidents at sea.